Top seed Rafael Nadal advanced to the Mexican Open quarter-finals in straight sets, while Alexander Zverev was a shock casualty.
Nadal – playing his first competitive tournament since the Australian Open – produced some highlight moments as he saw off Miomir Kecmanovic 6-2 7-5 in Acapulco on Wednesday.
A two-time winner of the ATP 500 event, world number two Nadal was a class above against his Serbian opponent to stay on course for the title.
After his powerful display, the 19-time grand slam champion will face Kwon Soon-woo for a spot in the semi-finals after the South African beat eighth seed Dusan Lajovic 7-6 (7-2) 6-0.
Australian Open semi-finalist Zverev was bundled out of the tournament by American qualifier Tommy Paul 6-3 6-4.
Zverev dropped his opening service game and it was a sign of things to come for the German star as Paul capitalised to eventually claim the biggest win of his career.
Next up for 22-year-old Paul is fifth seed John Isner, who downed fellow American Marcos Giron 6-3 7-6 (7-4).
Grigor Dimitrov saved two match points as he prevailed 6-7 (8-10) 6-2 7-6 (7-2) against Adrian Mannarino in a thriller.
Mannarino erased Dimitrov's 4-1 lead in the final set to earn a pair of match points but the Bulgarian rallied to set up a showdown with third seed Stan Wawrinka, who eased past Pedro Martinez 6-4 6-4.
Elsewhere, fourth seed Felix Auger-Aliassime was surprised 6-4 6-4 by Kyle Edmund and Taylor Fritz topped Ugo Humbert 6-4 6-1.
At the Chile Open in Santiago, seeds Casper Ruud, Hugo Dellien and Federico Delbonis all moved through to the quarters but Pablo Cuevas fell to qualifier Renzo Olivo.Published 27 Feb 2020, 13:06 IST